Sankey Diagram in Pandas

How to make Sankey Diagrams in Python with Plotly.

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See our Version 4 Migration Guide for information about how to upgrade.
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New to Plotly?¶

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We also have a quick-reference cheatsheet (new!) to help you get started!

Version Check¶

Plotly's python package is updated frequently. Run pip install plotly --upgrade to use the latest version.

In [1]:

import plotly
plotly.__version__

Out[1]:

'2.4.1'

Basic Sankey Diagram¶

In [2]:

import plotly.plotly as py

data = dict(
    type='sankey',
    node = dict(
      pad = 15,
      thickness = 20,
      line = dict(
        color = "black",
        width = 0.5
      ),
      label = ["A1", "A2", "B1", "B2", "C1", "C2"],
      color = ["blue", "blue", "blue", "blue", "blue", "blue"]
    ),
    link = dict(
      source = [0,1,0,2,3,3],
      target = [2,3,3,4,4,5],
      value = [8,4,2,8,4,2]
  ))

layout =  dict(
    title = "Basic Sankey Diagram",
    font = dict(
      size = 10
    )
)

fig = dict(data=[data], layout=layout)
py.iplot(fig, validate=False)

Out[2]:

Create Sankey Canvas¶

In [3]:

import plotly.graph_objs as go

plotly.offline.init_notebook_mode()

data = dict(
    type='sankey',
    domain = dict(
      x =  [0,1],
      y =  [0,1]
    ),
    orientation = "h",
    valueformat = ".0f",
    valuesuffix = "TWh"
  )

layout =  go.Layout(
    title = "Energy forecast for 2050, UK — Department of Energy & Climate Change",
    font = dict(
      size = 10
    )
)

Add Nodes¶

In [4]:

import plotly.graph_objs as go

import urllib, json

plotly.offline.init_notebook_mode()

url = 'https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy.json'
response = urllib.urlopen(url)
data = json.loads(response.read())

data_trace = dict(
    type='sankey',
    domain = dict(
      x =  [0,1],
      y =  [0,1]
    ),
    orientation = "h",
    valueformat = ".0f",
    valuesuffix = "TWh",
    node = dict(
      pad = 15,
      thickness = 15,
      line = dict(
        color = "black",
        width = 0.5
      ),
      label =  data['data'][0]['node']['label'],
      color =  data['data'][0]['node']['color']
    )
)

layout =  go.Layout(
    title = "Energy forecast for 2050, UK — Department of Energy & Climate Change",
    font = dict(
      size = 10
    )
)

Add Links¶

In [5]:

import plotly

import urllib, json

plotly.offline.init_notebook_mode()

url = 'https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy.json'
response = urllib.urlopen(url)
data = json.loads(response.read())

data_trace = dict(
    type='sankey',
    width = 1118,
    height = 772,
    domain = dict(
      x =  [0,1],
      y =  [0,1]
    ),
    orientation = "h",
    valueformat = ".0f",
    valuesuffix = "TWh",
    node = dict(
      pad = 15,
      thickness = 15,
      line = dict(
        color = "black",
        width = 0.5
      ),
      label =  data['data'][0]['node']['label'],
      color =  data['data'][0]['node']['color']
    ),
    link = dict(
      source =  data['data'][0]['link']['source'],
      target =  data['data'][0]['link']['target'],
      value =  data['data'][0]['link']['value'],
      color =  data['data'][0]['link']['color'],
      label =  data['data'][0]['link']['label']
  ))

layout =  dict(
    title = "Energy forecast for 2050, UK — Department of Energy & Climate Change",
    font = dict(
      size = 10
    )
)

fig = dict(data=[data_trace], layout=layout)
plotly.offline.iplot(fig, validate=False)

Style Sankey Diagram¶

In [7]:

import plotly

import urllib, json

plotly.offline.init_notebook_mode()

url = 'https://raw.githubusercontent.com/plotly/plotly.js/master/test/image/mocks/sankey_energy_dark.json'
response = urllib.urlopen(url)
data = json.loads(response.read())

data_trace = dict(
    type='sankey',
    domain = dict(
      x =  [0,1],
      y =  [0,1]
    ),
    orientation = "h",
    valueformat = ".0f",
    valuesuffix = "TWh",
    node = dict(
      pad = 15,
      thickness = 15,
      line = dict(
        color = "black",
        width = 0.5
      ),
      label =  data['data'][0]['node']['label']
    ),
    link = dict(
      source =  data['data'][0]['link']['source'],
      target =  data['data'][0]['link']['target'],
      value =  data['data'][0]['link']['value'],
      label =  data['data'][0]['link']['label']
  ))

layout =  dict(
    title = "Energy forecast for 2050, UK — Department of Energy & Climate Change",
    font = dict(
      size = 10,
      color = 'white'
    ),
    plot_bgcolor = 'black',
    paper_bgcolor = 'black'
)

fig = dict(data=[data_trace], layout=layout)
plotly.offline.iplot(fig, validate = False)

Reference¶

See https://plot.ly/python/reference/#sankey for more information and options!